Field of the Invention
The present invention is directed to controlling electromagnetic emissions. More particularly, the present invention relates to the stimulation of electromagnetic emissions to control pest populations.
Background Art
Stored grain is transported all over the world by ship, truck, and plane. The distribution of grain is dependent on short to long-term storage ranging from a few days to more than a year. The long-term storage of grain has encouraged the exponential growth of many insects and other pests that infest stored grain. Augmentation of pest populations are facilitated by the virtually unlimited food source found in storage grain bins or warehouses. Estimated losses caused by pests in temperate climates approximates 10-15%, but in tropical countries, the figure can be as high as 60%.
In less severe cases, healthy insect infestations, while not directly consuming the grain in bulk, greatly reduce grain marketability simply by their presence. Insect body parts or residues that can be found in storage grain samples thus create financial hardship for many farmers. On a national scale, this monetary figure runs into the hundreds of millions of dollars.
Farmers and industry have turned to chemical management in an effort to reduce the pest populations found in stored grain. The chemicals are either sprayed directly on the grain as it is being placed into the storage grain bin or warehouse storage area, or the same may be fumigated with a registered fumigant once the grain is placed in semi-permanent storage. The fumigant of choice for many years has been methyl bromide. However, methyl bromide is being phased out to comply with environmental regulations. Replacements for methyl bromide nonetheless are currently chemical in nature.
Several problems are associated with the chemical management of pest infested stored grains. These problems include chemical residues being left on grain destined for human or animal consumption, accidental human exposure to fumigants resulting in death or sickness, corrosive damage to sensitive equipment such as computers, and the potentially high financial costs of fumigation, most especially at ports. These are serious problems that all present and future fumigation companies must address.
An alternative to chemical management is the use of insect traps that contain naturally attractive molecules called pheromones. Typically, these molecules are released into the atmosphere by individual insects and are used by insects to locate a mate. For this reason, these particular molecules are called insect sex pheromones. When pheromones were first synthetically produced in the 1960s, many believed they would solve pest management problems since sex pheromones were considered to provide an irresistible and highly specific attractant to many of the most common insect pests. Unfortunately, the sex pheromone traps did not meet their expectations. Because they attract so few insects, these traps have been downgraded from insect management devices to merely insect monitoring devices.
Current sex pheromone traps have many limitations. One limitation includes the relatively small number of insects trapped over a given period of time. There are no reliable figures to specify the percentage of insects that can be successively trapped in a given area. However, years of research wholly supports that the traps are ineffective at significantly reducing insect populations in a storage grain bin or warehouse unless the traps are used in very high densities.
A second limitation is the reduced longevity of the pheromone source or lure in conventional traps. The longevity of the pheromone lure is estimated to be approximately six weeks based on anecdotal information in the industry. A third limitation involves the mechanism used by these pheromone traps to capture and retain the insects. A sticky card is a common mechanism used to hold and retain the insects once they enter the pheromone trap. However since pheromone traps are often placed in dusty environments, a sticky card can become useless after only a few days, which is unfortunately long before the pheromone lure will lose its effectiveness.
An exemplary insect trap is described in U.S. Pat. No. 3,997,785 to Callahan (herein referred to as the '785 patent), which is incorporated herein by reference as though set forth in its entirety. This trap functions by vibrating a gold coated needle in a molecular scent vapor. Although it provides advantages over other conventional solutions, this trap did not perfectly mimic the frequencies produced by the target insect. Improvements were made and described in U.S. Pat. No. 5,424,551 to Callahan (herein referred to as the '551 patent), which is incorporated herein by reference as though set forth in its entirety. Despite the advantages this trap has over other conventional solutions, this trap has been determined to attract insects at a distance of only four to five centimeters.
Consequently, a system and method are needed to solve the above-identified problems and provide an efficient solution for controlling insects and other pests without the harmful side-effects of chemical management.